The present invention relates to a Mandarin speech input method for Chinese computers and a Mandarin dictation machine, in particular to a method in which Mandarin speech is used for inputting Chinese characters into computers, and a machine which converts the spoken Mandarin sentences into Chinese characters and displays them on the screen of a monitor.
Today, the methods of inputting Chinese characters into computers are numerous, for instance, those based on the pronunciation thereof, or based on word roots, or strokes. However, none of these methods have been recognized as a very convenient method of inputtings, because the inputting procedure is much less efficient as compared to those for alphabetic languages such as English. Some methods of inputting require special long term training, while other methods may be comparatively slow, or require memorizing numerous rules which may be easily forgotten as a result of infrequent use. For instance, the "phonetic symbol input method" is easily practised by everyone but the speed of keying is too slow. The fastest input methods are the "word root methods" such as Tsang-jiieh method. But, this method can only be used by those who have undergone a long term of input training This method may be forgotten if not frequently used and is inconvenient due to the fact that the Chinese characters have been intentionally modified so as to correspond to several of the keys of the keyboard In any case, the keyboard is initially designed for the alphabetic languages such as English and it is, therefore, inconvenient for keying Chinese characters.
The method of inputting Chinese characters by way of speech has long been proposed. In any case, the technique of inputting Chinese characters based on speech faces difficulties which are almost impossible to overcome. These difficulties are as follows:
(1) The necessary vocabulary for the Chinese language is too large for speech recognition technology. The Chinese characters commonly used are at least 15,000 and the commonly used Chinese words are at least 40,000;
(2) Large numbers of homonym characters exist for almost every pronunciation in Mandarin. That is, even though the pronunciation is correctly recognized, it is still difficult to obtain the exact characters; PA1 (3) The transformation from Mandarin speech into Chinese characters has to be completed in real-time for the input method to be practically used.